1. Field of the Invention
The embodiments disclosed in this application generally relate to methods, apparatuses, and systems for generating multiple laser pulses in short succession for use in laser induced breakdown spectroscopy systems to characterize materials via spectrochemical analysis.
2. Background of the Invention
Laser induced breakdown spectroscopy (LIBS) is an analytical method that uses a laser to ablate and ionize a sample, forming a plasma from which light emitted from the plasma can be analyzed to identify the elemental constituents of the sample. LIBS techniques are well suited for field analysis since only the laser beam must reach the sample. This is especially advantageous for remote sample monitoring of hazardous materials or materials located in difficult to reach locations. Lasers systems suitable for use in LIBS systems typically have good spatial beam quality and a high enough pulse energy to adequately ionize the material being analyzed, which is particularly important when the sample being analyzed has a relatively large standoff distance from the LIBS system.
LIBS systems using conventional laser systems have resulted in issues with high detection limits (typically >1 ppm), reproducibility of results, and interference due to matrix effects (that is low signal to noise ratios that interfere with the analysis). Many of these issues can be traced back to the variations in the laser spark and resultant plasma process due to shortcomings with the laser systems used. In short, existing laser systems used in LIBS systems and methods for spectrochemical analysis fail to provide the optimal detection limit, reproducibility, and signal to noise ratio parameters required for achieving optimal real time spectrochemical hazard analysis in the field.